Chronic mainly respiratory bacterial disease but can affect almost any other organ, caused by Mycobacterium tuberculosis (also M.bovis/africanum,microti), exposure does not always = infection, can be fought or latent.

Inhaling infected droplet nuclei from a cough/sneeze by infected person (from their granuloma in lung tissue)

Microscopy (quick and done on any sample but low sensitivity and specificity)

Culturebut takes a long time, needs wide range of growth conditions, some unable to culture. Media: solid or liquid, if need time = contamination.

Automated systems: lq culture media, continuously monior and flag up real time new +ves, decreased workload, can be used for susceptibility testing, measures O2 consumption/CO2 production but single incubation temperature

Skin test, see if previous TB infection. Inject extract of mycobacterium antigens and measure reaction 48-72hrs later. If v marked, may have TB. Now can do it via blood: take lymphocytes and stimulate with same antigens from Mantoux test -> produce interferons if respond (IGRA).